Short for 'All Your Base Are Belong To Us', or sometimes 'AYB' (All Your Base), stemming from a phenominon started from a poorly translated Japanese-to-English version of the Japanese Genesis game 'Zero Wing'.

Captain: What happen ?
Mechanic: Somebody set up us the bomb.
Operator: We get signal.
Captain: What !
Operator: Main screen turn on.
Captain: It's you !!
Cats: How are you gentlemen !!
Cats: All your base are belong to us.
Cats: You are on the way to destruction.
Captain: What you say !!
Cats: You have no chance to survive make your time.
Cats: Ha Ha Ha Ha ....
Operator: Captain !!*
Captain: Take off every 'Zig'!!
Captain: You know what you doing.
Captain: Move 'Zig'.
Captain: For great justice.

Many online gamers began using these phrases in channels,thus leading to many photoshopped pictures saying phrases from the above dialogue.

Somebody Set Up Us The Bomb = Holy Sh*t
All Your Base Are Belong to Us = We Won
Move 'ZIG' = General Action Command
For Great Justice = Self Explanitory

The above phrases became 'universally known' as those commands in many OL Games such as Counterstrike, and Warcraft. The real translation is basically:
Oh crap someone set up bombs. Were getting a transmission. Ill put it on the main screen. Its you! How are you gentlemen? We have captured all of your bases. You have no chance to survive. Move all ZIG! For great justice!

(NOTE: ZIG are the small ships the player pilots in ZW)

The AYB Phenominonn has been declared dead a while ago, but Im bored so I posted this...

AYBABTU or known as "All your base are belong to us" from the 1991 japanese sega genesis game "Zero Wing"..
It has spreaded very widely all over the world.
more details can be found at www.allyourbasearebelongtous.com

Cats: (AYBABTU) All your base are belong to us!
Cats: You are on the way to destruction

Captain: What happen ?
Mechanic: Somebody set up us the bomb.
Operator: We get signal.
Captain: What !
Operator: Main screen turn on.
Captain: It's you !!
Cats: How are you gentlemen !!
Cats: All your base are belong to us.
Cats: You are on the way to destruction.
Captain: What you say !!
Cats: You have no chance to survive make your time.
Cats: Ha Ha Ha Ha ....
Operator: Captain !!
Captain: Take off every 'Zig'!!
Captain: You know what you doing.
Captain: Move 'Zig'.
Captain: For great justice.

Translation:

Captain: What happened?
Mechanic: Someone set up bombs.
Operator: We are recieving a signal.
Captain: What?
Operation: Turning on the main screen.
Captain: It's you!
Cats: How are you, gentlemen?
Cats: All of your bases now belong to us.
Cats: You are on the way to destruction.
Cats: You have no chance to survive, live while you can.
Cats: HA HA HA !!!!
Operator: Captain?
Captain: Zigs, take off!
Captain: You all know what you are doing.
Captain: Move, Zigs.
Captain: For great justice...

Your basis everything which starts with the wing of AYBABTU, or mistranslated video game zero belongs, there are Internet phenomenon we who are. That dies, still floarting parody it can look at 2.

Captain: It's you !!
Cats: How are you gentlemen !!
Cats: All your base are belong to us.
Cats: You are on the way to destruction.
Captain: What you say !!
Cats: You have no chance to survive make your time.
Cats: Ha Ha Ha Ha ....

Short for 'All your base are belong to us', meaning something like 'we own you' or 'you got owned' or something. anyway. The popularity of this phrase is unexplainable but it has circulated the net for years in pictures and text. Originally comes from a game for the sega megadrive system called zero wing, a space shoot-em-up released in japan in the '80s. The game was translated into english (very poorly at that, it almost qualifies as engrish) and released in europe in 1989. For more details on how this phrase came to be, google for 'AYBABTU'.

a picture of a tank getting blown up by a huge missile would be captioned 'aybabtu'.